On the Gas Adsorption & Desorption Characteristics for Some Turkish Lignites in Terms of Coal Quality Parameters

Gas sorption capacity in coals is a well-researched topic, yet the complexity of experimental setups often limits detailed reporting. Understanding coal gas adsorption and seam gas content is essential for predicting and preventing mine gas outbursts and explosions. Therefore, characterizing coal samples based on their adsorption capacities is crucial. This study explores the adsorption of nitrogen, carbon dioxide, and methane across different coals and plots isotherms to assess the impact of gas type, pressure, and coal quality parameters. Results indicate that methane can adsorb even at low pressures in the Dursunbey sample, while higher pressures are required for carbon dioxide and nitrogen. The study also finds a strong correlation between Langmuir volume and ash percentage on an original basis, with nitrogen showing the highest correlation (R² = 0.7), followed by methane (R² = 0.69). Carbon dioxide, however, exhibits a weaker correlation (R² = 0.44).